I had code for umap’s working on 4.10 using :
FCoreDelegates::OnMountPak // and
IFileManager::Get().FindFilesRecursive(mapFiles, FPaths::GameContentDir(), TEXT(".umap"), true, false);
But it’s no longer working :(. I did a bit of debugging and diffing source files, but haven’t found the regression yet. I’ll take another pass at this later, but need to get other things done for the moment.